Types of genetic testing and their advantages and disadvantages
| Test type . | Advantages . | Disadvantages . | Example of best use . |
|---|---|---|---|
| Sanger sequencing (single gene) | • Less expensive | • Only provides information on one gene | Confirmation of known variant in affected family |
| • Fast turnaround | |||
| Gene panel | • More in-depth coverage of genes of interest | • Does not interrogate genes outside of panel (may miss novel associations) | Clinical scenario provides suspected diagnosis for confirmation |
| • Custom designed to disease of interest | • Utility depends on frequency of panel update | ||
| • No secondary findings | |||
| • Generally faster turnaround | |||
| Whole exome | • Agnostic and comprehensive | • Insensitive to deletions/duplications, depending on technique | Novel syndrome unclear diagnosis |
| • Allows identification of novel variants | • Reading depth influences ability to find variants in some genes | ||
| • May be more readily available (not custom) | • Expensive | ||
| Whole genome | • Allows sequencing of noncoding regions | • Expensive | Suspected genetic disease due to noncoding variant |
| • Better than WES at detecting indels/duplications/inversions | • Lower read depth for some areas | ||
| CGH array | • Detects large genomic changes | • Insensitive to single-nucleotide changes | Chromosomal deletions, loss |
| Test type . | Advantages . | Disadvantages . | Example of best use . |
|---|---|---|---|
| Sanger sequencing (single gene) | • Less expensive | • Only provides information on one gene | Confirmation of known variant in affected family |
| • Fast turnaround | |||
| Gene panel | • More in-depth coverage of genes of interest | • Does not interrogate genes outside of panel (may miss novel associations) | Clinical scenario provides suspected diagnosis for confirmation |
| • Custom designed to disease of interest | • Utility depends on frequency of panel update | ||
| • No secondary findings | |||
| • Generally faster turnaround | |||
| Whole exome | • Agnostic and comprehensive | • Insensitive to deletions/duplications, depending on technique | Novel syndrome unclear diagnosis |
| • Allows identification of novel variants | • Reading depth influences ability to find variants in some genes | ||
| • May be more readily available (not custom) | • Expensive | ||
| Whole genome | • Allows sequencing of noncoding regions | • Expensive | Suspected genetic disease due to noncoding variant |
| • Better than WES at detecting indels/duplications/inversions | • Lower read depth for some areas | ||
| CGH array | • Detects large genomic changes | • Insensitive to single-nucleotide changes | Chromosomal deletions, loss |
CGH, comparative genomic hybridization; WES, whole-exome sequencing.